1. Field of the Invention
The invention generally relates to a system and method of bin allocation and, more particularly, to a system and method for dynamically allocating bin assignments during a sort process.
2. Background Description
The sorting of mail is a very complex, time consuming task. In general, the sorting of mail is processed though many stages, including back end processes, which sort or sequence the mail in delivery order sequence. These processes can either be manual or automated, depending on the mail sorting facility, the type of mail to be sorted such as packages, flats, letter and the like. A host of other factors may also contribute to the automation of the mail sorting, from budgetary concerns to modernization initiatives to access to appropriate technologies to a host of other factors.
In general, however, most modern facilities have taken major steps toward automation by the implementation of a number of technologies. These technologies include, amongst others, letter sorters, parcel sorters, advanced tray conveyors, flat sorters and the like. As a result of these developments, postal facilities have become quite automated over the years, considerably reducing overhead costs.
But, in implementation, many of these systems are constrained by their physical limitations. For example, currently, it is known to sequence letters using a mail sorter having a number of physical bin locations, e.g., about 100 bin locations. So, when sorting the mail, only 100 bin locations can be used regardless of the size of the delivery route, density of the delivery route and other considerations. Of course, though, other known number of bin allocations can equally be used to sort letters, a host of them readily available and known to those of ordinary skill in the art.
In use, each bin location has a tray or container associated with the bin location, itself, for storage of the mail pieces during the sorting process. For example, during the sorting of mail pieces such as flats (e.g., magazines, newspapers and the like), each of the mail pieces for a particular delivery route and more specifically a segment of a delivery route is inducted into a specific pre-allocated bin location. In the bin location, a tray is provided for storing of the mail piece prior to delivery. In a typical system, the tray is capable of holding between 65 and 85 flats, depending on the size of the flats.
But, these systems are preprogrammed with a bin allocation for a specific route or sort plan, for example, in advance of the sorting process. These bin allocations are typically provided based on historical data for that specific route and stored in a look-up table. By way of illustration, the system is programmed based on a density of mail pieces for a particular segment of a delivery route. The “high density” portion of the route would be allocated to the most easily accessible bin locations in order to make it easier for an operator to manually unload the tray and place a new tray in its place for further mail induction. In other words, the programmer or technician, based on historical data, can segment the bins into “break out” sections for a particular neighborhood or delivery route.
But, these systems and sort plans cannot take into consideration many situations that may impact the efficiency of the system. For example, once a sort plan is defined ahead of time, it cannot be changed during the sorting operation. Thus, if the density pattern changes for a particular day, the system still remains constrained to the pre-programmed sort plan. This may lead to an inefficiency in the system by having bin locations allocated to lower density routes bearing the burden of higher density sorts, despite historical trends.
Although the sort plan itself cannot be changed, the operator has the ability to assign a specific bin to another location through a manual operation by identifying. This can override the sort plan definition for the duration of the run, or until changed. But, this manual process is too slow to feasibly address any real-time dynamic allocation, and it is a function of the operator's selection, as opposed to a system decision based on system knowledge.
Additionally, in order to utilize known systems and sorting plans, each tray within a bin location has to be physically removed and replaced upon filling of such tray. This is referred to as a “swap”. To accomplish this swap, the operator may manually remove the trays and exchange such tray with an empty tray within that bin location. This process may also be automated. But during this swap there may be a delay in placing a new tray in the bin location. Thus, one of three situations may result:                (i) the bin location may have to be disabled so to avoid mail spillage; or        (ii) the bin location is not disabled and mail spillage occurs; or        (iii) there is a mail jam resulting from mail spillage or other user induced incidence resulting from the swap.In any of these situations, the potential for impacting the ability to sort mail pieces properly is greatly increased. In other words, the efficiency of the system can be greatly reduced during this swap process.        
Additionally, due to the complexity of these sorting systems, there is a possibility that an actuator, pneumatic device or other mechanical system (used to induct mail into the trays) may fail or wear down during the sorting operations. When these devices wear down or fail (or misfire), a greater error rate will occur thus, again, impacting the efficiency of the system. That is, the associated bin location will no longer be available thus reducing the throughput of the system.
In current systems, these error rates may be monitored. However, to compensate for these error rates, the sort order has to be manually adjusted, by disabling a particular bin location and manually reallocating it to another bin location. This is a complex procedure and cannot be performed during the sorting operations. Thus, the system is taken off-line, reprogrammed and then placed back into service. In the alternative, there may be a manual override of the sort plan to reallocate the bins, as discussed above. In either situation, this is very labor intensive, adding to the downtime and hence inefficiency of the system.
The invention is directed to overcoming one or more of the problems as set forth above.